PIPES
PIPES is the common name for piperazine-N,N′-bis(2-ethanesulfonic acid), and is a frequently used buffering agent in biochemistry. It is an ethanesulfonic acid buffer developed by Good et al. in the 1960s.[1]
Names | |
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Preferred IUPAC name
2,2′-(Piperazine-1,4-diyl)di(ethane-1-sulfonic acid) | |
Other names
PIPES | |
Identifiers | |
3D model (JSmol) |
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ChemSpider | |
ECHA InfoCard | 100.024.598 |
PubChem CID |
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UNII | |
CompTox Dashboard (EPA) |
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Properties | |
C8H18N2O6S2 | |
Molar mass | 302.37 |
Appearance | White powder |
Melting point | Decomposes above 300 °C |
Boiling point | Decomposes |
1 g/L (100 °C) | |
Hazards | |
Occupational safety and health (OHS/OSH): | |
Main hazards |
Irritant |
NFPA 704 (fire diamond) | |
Safety data sheet (SDS) | External MSDS |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references |
Applications
PIPES has two pKa values. One pKa (6.76 at 25 °C) is near the physiological pH which makes it useful in cell culture work. Its effective buffering range is 6.1-7.5 at 25 °C. The second pKa value is at 2.67 with a buffer range of from 1.5-3.5. PIPES has been documented minimizing lipid loss when buffering glutaraldehyde histology in plant and animal tissues.[2][3] Fungal zoospore fixation for fluorescence microscopy and electron microscopy were optimized with a combination of glutaraldehyde and formaldehyde in PIPES buffer.[4] It has a negligible capacity to bind divalent ions.[5]
References
- Good, Norman E.; Winget, G. Douglas; Winter, Wilhelmina; Connolly, Thomas N.; Izawa, Seikichi; Singh, Raizada M. M. (1966). "Hydrogen Ion Buffers for Biological Research". Biochemistry. 5 (2): 467–77. doi:10.1021/bi00866a011. PMID 5942950.
- Salema, R. and Brando, I., J. Submicr. Cytol., 9, 79 (1973).
- Schiff, R.I. and Gennaro, J.F., Scaning Electron Microsc., 3, 449 (1979).
- Hardham, A.R. (1985). "Studies on the cell surface of zoospores and cysts of the fungus Phytophthora cinnamomi: The influence of fixation on patterns of lectin binding". Journal of Histochemistry. 33 (2): 110–8. doi:10.1177/33.2.3918095. PMID 3918095.
- "Hopax Fine Chemicals - Biological buffers and their interactions with metal ions".